Who’s got pics on how a round duct *cuts-fits* into a rectangular duct….It’s a long story but I’ve got a unique kitchen duct situation and I must have called every single mechanical guy and only 2 responded.
1st rep was a joke…..speced my aluminum duct, lightweight, etc
2nd rep came out, seemed great, no-nonsense guy but I’m a lil bit unsure on his workmanship……..
I’ll try to get some pics but’s it was a matter of getting the fit good and the transition from the hood (round) to rectangular – I don’t think it’s good. He’s slated to come back but he told me it’s not a problem since he’s going to wrap it up in mastic tape and then apply duct mastic.
Replies
Chefwong;
It's not normally a problem.
Go to a decent sheet metal shop, tell them what the dimensions are and they will get you a transition piece. Hopefully there's some space between them and you aren't trying to just jam one into the other.
Don K.
EJG Homes Renovations - New Construction - Rentals
Here's the scoop. From the top of the hood to the ceiling is about 12"My duct is speced at 14" x 4" High.He seems like a great guy....I think I will need to discuss with him because every way I look at it, it is wrong, wrong, wrong. And I have tried all the mechanical guys but I think my job is too small for them.....The reason why my duct is 4" high is because it sits ontop of my cabinets. It's a short run. Goes vertical about a feet, makes a 90 ontop of the cabs about 3 feet, then turns and makes another 90 for 18 inches and makes another 90 out to the back of the house.The hood has a stock 7" round. It's a 4x6 cutout with a 7" round plate on it.
I just took a look and this is what he did...and I can't see the reasoning why. The vertical pipe that sits on my hood is 9" Dunno why but I assume if it sits flush on the hood and it's sealed tight to the hood, it's not a problem ???My issue is when he tried fitting in the vertical piece from the hood to the 1st long run. He cut the hole into the 14" x 4" duct - but it did not line up so he ended up cutting MORE. It's closer to a 10 - 10.5" hole where the 9" round is going into it.I am not sure how he's going to seal this thing or even if he does, will it be reliable.HELP - advice please.
I know that I will have to talk and reason with him about this.....I have called every mechanical guy in the yellowpages. Spoke with a couple, faxed in my layout, specs, etc and not a peep. It's not like I had alot of choices when finding someone to do this scope of work.....
They probably don't want to fool with such a convoluted route and all of the 90's. these will kill your ventilation ability.
Move your hood closer to the outside wall. Or go straight up thru the roof (if possible). How do the ceiling joists run? You may have to rip out the ceiling drywall and run it between the joists and then out. I can't quite vision the looks of a duct running on top of cabinets.
For best performance, you need the shortest line and the fewest bends. Or suffer a serious decrease in flow and increase in noise level.
I hear ya on the 90's but this is the only path it can take !
It cannot go straight due to chimney stack. This it takes the corner for a short bit and then it makes the 90 out.
Time for a kitchen remodel.
With what you are thinking, I promise you won't like the results.
The stock duct is 7"I spoke with Broan tech support extensively and they took the measurements , length of the duct runs, two 90's and according to their calculator....I was advised the volume, static pressure, etc looked fine.I know the straightest path is the best path but I'd like to hear some more why you thing it's totally wrong.....
Scan your layout and specs and post them here.
I suspect that you need a transition flanged 4x6 oval (or 6 or 7"round) with 90 to 14W x 4H with slip in fit.
Any sheet metal shop can fabricate one in an hour or less.
They will need to know the horizontal distance from the center of the hood opening to the edge of the rectangular duct after you cut the 10.5" holed section off, and the vertical distance from the hood opening to the bottom of the rectangular duct.
They will also need to know the direction and offset (relative to the back of the hood) of the exact centers of each.
Measure the transitional piece to slip 2" into the rectangular duct. Design it to slip in 3". This will allow you to line everything up. and still get at least 1" slipped in.
The better shops will also build a slip joint into the vertical oval (round) section.SamT
Here is a picture, is this what your talking about? Just add a round elbow to it?
picture please? It would be oh so helpful to see what ya got.